I dont know what to do...

I've been with my employer for 4 years this October. Not long after I started my postion in the company which was customer service. I became very ill and had to be off of work due to my illnesses. I filed an STD claim and was denied, I have finally taken care of that issue, so far. I was on a LOA due to being disabled and not qualifying for FMLA. Anyway, I came back to work after being off for awhile and was promoted due to performance. In that time a man who I work with sexually propositioned me and I reported it to my boss and HR. I was still having medical issues and went back out on leave and upon my return, this guy that propositioned me came and cornered me in the break room and tried to get me into an office. I immediately reported it to my supervisor and followed up with HR on Monday, since it was the weekend. I was told by HR to apply for a position to go to a different dept, so that I would not have contact with him. Anyway, I was denied the position. I did go out on leave because that kind of stress was causing issues, since I have to report to this guy for any type of escalation. My work did settle with me for a small cash award and a promotion to a new position. I started the position and the day I arrived the company stated that I would be in a different building than the employee that was doing the harassing and I was told to go back into the building where this guy was and brought it to the attention of HR and they were upset and we had a heated argument on the phone and almost two weeks later I had a stroke. I am off on STD right now. Can my employer fire me? They are already giving me a hard time, but the doctor will not release me until I can see a neurologist which is 2 weeks.